1. Field of the Invention
This invention relates to a tampon and more particularly to a tampon configured for easy insertion and removal, and having regions of spermicides, anti-infectives and lubricants placed within the tampon.
2. Background of the Relevant Art
It is well known that in recent years there has been a steady increase in the number of sexually transmitted diseases (STDs) and unwanted pregnancies in the U.S. and throughout the world. In an effort to stem the rise of unwanted pregnancies, many types of contraceptive devices are being utilized. Oral contraceptives and intrauterine devices (IUD) are two very popular contraceptive methods. However, not all women are capable of using oral contraceptives, and IUDs produce many documented side effects. Other types of contraceptives, or barrier contraceptives, have gained in popularity due to the rise of STDs. Popular barrier contraceptives include condoms, diaphragms, sponges, cervical caps, spermicidal creams, foams, foaming tablets, films and melting suppositories. A diaphragm and cervical cap must be fitted by trained medical personnel, whereas condoms require the participation of the partner. Foams, jellies, tablets and suppositories are often messy to use, and frequently cause irritation to the user and/or partner.
Developments in contraceptive methods allow a barrier, such as a sponge or tampon, to be impregnated with a spermicide. The impregnated barrier not only physically prevents the passage of sperm or STDs, but also chemically kills the sperm or infective agents associated with many STDs. A time-release spermicide can allow a single impregnated tampon to kill sperm throughout numerous sexual encounters and over a relatively long period of time.
As described in U.S. Pat. No. 4,393,871, gradual release of spermicide from a tampon can be achieved by placing the spermicide into the pre-polymer material during the polymerization of the tampon. The spermicide/surfactant is thereby molded to form the polyurethane tampon. In order to activate the tampon of Patent '871, tap water must be added at the site. Too large an amount of water can unduly dilute the spermicide, such as nonxylphenoxypoly (ethyleneoxy) ethanol, or "nonoxynol-9", possibly rendering it ineffective Further, tap water at the site may be contaminated, or may contain chlorine which could possibly interfere with the nonoxynol-9 or cause infection. Conversely, too small an amount of water can cause a strong presence of nonoxynol-9, leading to irritation and allergic reaction as described in U.S. Pat. No. 4,693,705.
As taught in Patent '705, recent advances suggest a more controlled concentration of spermicide, such as nonoxynol-9. Accordingly, it is advantageous that the spermicide be placed already in solution within the sponge and at controlled concentration such that the spermicide is active and ready to use at the site. Mixing with tap water is therefore not required.
Impregnating a sponge with a solution such that it is ready to use at the site presents many advantages described above. However, the soaked tampon must maintain its shape as a physical barrier while packaged and during insertion. Further, it also must withstand shear forces during placement and subsequent removal. Current sponges which use a single string placed through only a portion of the sponge material can pull through the sponge upon removal. Examples of sponges which use only a small portion of their geometry for receiving a string or tied loop are described in U.S. Pat. Nos. 4,186,742; 4,309,997; and 4,693,705. Another exemplary attachment scheme showing a loop affixed to the outside surface of the sponge is taught in U.S. Pat. No. 4,393,871. A slight pull upon the string or loop can cause a single string shown in Patents '742 and '997 to pull through the body, can cause a loop shown in Patent '871 to pull from the body's outer surface, or a knot and surrounding small portion of the body shown in Patent '705 to dislodge from the body. A future source of infection may arise if any portion of the sponge material is allowed to remain in the body cavity for an extended period of time. "Toxic shock syndrome" may arise in instances where an infective site is allowed to remain within a body cavity, such as a vaginal canal, for an extended period of time.
A properly inserted and removed sponge or tampon not only enhances the benefits of the device, but also maintains long-term effect while positioned. Ease of positioning or insertion is equally important as maintaining the sponge's integrity during removal. A sponge, having a doughnut or flattened shape as shown in Patent '871 may easily fold thereby failing to present equal radial pressure against the cavity wall. A passage may therefore be formed in those areas voided of pressure as a result of the fold. An optimal shape appears to be spherical ball having radially expandable pressure against all sides of the cavity wall. However, the spherical ball will oftentimes be compressed to an outer dimension much less than the original expanded dimension during placement. As a result, spermicide impregnated within only the outer portion of the sponge may be flushed or squeezed from the sphere during placement. Absence of spermicide can thereby lead to an ineffective contraceptive device.
As defined herein, "spermicide" is a chemical placed in solution, and which provides a chemical barrier against sperm and sexually transmitted organisms responsible for STDs. Therefore, "spermicides" used herein include an anti-infective agent. Spermicide have, in many instances, been found to be active against herpes, gonorrhea, syphilis, trichomonas, candida, and even HIV. Popular spermicides include benzalkonium chloride, chlorhexidine, gluconate, menfegol, octoxynol and, as described above, nonoxynol-9. Nonoxynol-9 is a spermicide which acts by destroying the cell wall of the sperm, and is believed to act in the same manner on bacteria and viruses. Because it destroys the cell wall of sperm, bacteria and viruses, it can also cause some local irritation in both men and women using the product improperly, or in large dosages.